Hi Bob,
thanks for returning from your well-deserved retirement to answer this question and providing insight into the -cenmode NTRP interpolation option! I have always wondered what the reference to the Spanish Inquisition in the -help file of 3dTproject meant... now I not only understand the method better but I know one more bit of AFNI trivia.
I agree that it's not ideal to have the impression that you're dealing with a data set of 100% real data but as you mentioned, for some inter-subject analyses it's a necessity to have equal lenght of time series. But we will keep this limitation in mind for our analyses and transparently communicate the choice and method of interpolation in our manuscript.
Jonas
